Generally speaking, the square tube of the finished product that has been processed has a small degree of tortuosity, or it depends on the proofreading of the machine. Generally, to eliminate the bending of the square tube, it is necessary to pass the cold straightening, and the square tube The bending may be due to the fact that the mill is not adjusted for adjustment. Therefore, the remaining force in the rolling is formed by cooling or the like along the section and length of the pipe. Therefore, it is not possible to use a rolling mill to directly obtain a very straight pipe, and it is necessary to pass the cold straightening pipe to satisfy the non-bending of the pipe.

　　The fundamental principle of straightening is to make the square tube elastically and tortuous, and the large tortuosity becomes a small tortuosity, so the steel tube needs to be repeatedly twisted and twisted in the straightening machine. The degree of repeated twists and turns of the steel pipe is mainly determined by the adjustment of the straightening machine.

　　There are many factors that affect the quality of straightening, such as the tortuosity of the original pipe, the size of the steel pipe and the type of material straightening machine, and the adjustment parameters.